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This paper describes magnetron reactive ion etching (RIE) characteristics of polycrystalline
(poly) 3C-SiC thin films grown on thermally oxidized Si substrates by atmospheric
pressure chemical vapor deposition (APCVD). The best vertical structures were obtained by the
addition of 40 % O2, 16 % Ar, and 44 % CHF3 reactive gas at 40 mTorr of chamber pressure. Stable
etching was achieved at 70 W and the poly 3C-SiC was undamaged. These results show that in a
magnetron RIE system, it is possible to etch SiC with lower power than that of the commercial RIE
system. Therefore, poly 3C-SiC etched by magnetron RIE has the potential to be applied to
micro/nano electro mechanical systems (M/NEMS).

Abstract: Inductively coupled plasma reactive ion etching of Ge doped silica glasses and SiON was
investigated, using C2F6- and NF3-based gas mixtures. Mesas with smooth surfaces and vertical
sidewalls were obtained, with a maximum etch rate of about 310nm/min in the case of C2F6 RIE of
Ge-SiO2 and 280 nm/min in the case of SiON. The NF3 plasma yielded slightly higher etch rate,
although sloped sidewalls were obtained. Results of the X-ray photoelectron spectroscopy showed
little contamination on the etched surfaces.

Abstract: In order to realize complex three dimensional or free standing structures on SiC substrates, an undercut, i.e. a selective isotropic etching process of SiC, is required. This was realized using an electron cyclotron resonance etching set up with pure SF6 and a SF6/Ar gas composition at elevated substrate temperatures. Above 350°C a significant lateral etch component was observed, which rose to a value of 50-70 nm/min increasing the substrate temperature up to 570°C during the etching process. Depending on substrate temperature the etching profiles and surface roughness were studied. Based on an analysis of the influence of microwave power, working pressure, bias voltage, gas flow and gas mixture on the etching behavior a novel isotropic, high selective, residue free etch process for SiC was developed, which allows for example the fabrication of piezoelectric actuated AlGaN/GaN resonators grown on SiC substrates.

Abstract: Trench structure etching is one of the most important processes for the fabrication of 4H-SiC Trench MOSFETs. This paper introduced Al2O3 as an etching mask for the fabrication of trench structures. The effect of dry etching parameters to the shape of trench structures were studied systematically. Micro trenches were successfully eliminated from trench structure etching process and preliminary trench MOSFET test structures were fabricated and characterized.